<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
      *{
        margin: 0;
        padding: 0;
    }

    ul{
        width: 200px;
        height: 200px;
        background: orange;
        list-style: none;
        display: flex;
        align-items: center;
        flex-direction: column;
    }

    li{
        width: 50px;
        height: 50px;
        background: pink;
        margin: 5px;
    }
    </style>
</head>
<body>
    <ul>
        <li></li>
        <li></li>
        <li></li>
    </ul>
</body>
</html>